This invention relates to a document feeding apparatus including a latch mechanism for locking the feeder over a transparent platen. The apparatus is particularly adapted for use in a reproducing machine.
Numerous document feeders for use with reproducing machines are known as exemplified by U.S. Pat. Nos. 3,499,710, granted Mar. 10, 1970, to Sahley; 3,556,512, granted Jan. 19, 1971, to Thackler; 3,674,363, granted July 4, 1973, to Baller, et al; and 3,790,158, granted Feb. 5, 1974, to Summers et al. These patents are representative to the broad prior art in this area directed to document feeders for placing a document on transparent viewing platen for viewing by the optics of a reproducing machine for making copies of the document. The first named patent shows the use of friction rolls for transporting the document over the platen and the remaining patents show the use of a belt type transport device.
An alternative type document feeder for use with a reproducing machine is that set out in U.S. application, Ser. No. 367,996, filed June 7, 1973, to Hoppner. In accordance with the subject application, a scanning optical system is fixed adjacent one margin of a transparent viewing platen and a document feeder is positioned overlying the optics to advance documents past the fixed optical system at a speed synchronized to the speed of an image receiving member.
Document feeders for xerographic reproducing machines have been used commercially in machines produced by Xerox and IBM. In the IBM Copier II, the document feeder mechanism is held in the feeding position by a hook type latch. When a lift handle is raised, it releases the latch allowing the document feeder mechanism to raise under spring tension. Alternatively, a solenoid is provided for automatic release of the latch after certain operations. In U.S. Pat. No. 3,642,271, granted Feb. 15, 11972, to Jones et al, a platen cover latch mechanism is described wherein a hook type latch is provided which may be released by manually depressing a button or through the use of a solenoid.